1. Cisco Internetworking Revision Sheet
Basic Router Operations
To get to User Mode Press ENTER and a password if required.
To get to Privileged Mode Router>enable
To get back to User Mode Router#disable
To Exit the Router Router>exit or logoff
Break Key <shift>+<ctrl>+6 ‘x’
To move to the beginning of the command line Ctrl+A
To move to the end of the command line Ctrl+E
To move forward one character Ctrl+F [or right arrow key]
To move back one character Ctrl+B [or left arrow key]
To repeat the previous command Ctrl+P [or up arrow key]
To repeat the most recent (last) command Ctrl+N [or down arrow key]
To move back one word Esc+B
To move forward one word Esc+F
To erase a word Ctrl+W
To erase a line Ctrl+U
To redisplay a line Ctrl+R
Ends configuration mode and returns to privileged mode Router#Ctrl+Z
To auto complete a command <tab>
To show the command buffer Router>show history
To set the command buffer size Router>terminal history size
To disable advanced editing features Router>terminal no editing
To re-enable advanced editing features Router>terminal editing
Viewing Router Information
View IOS version Router#show version
View current configuration file (RAM) Router#show running-config
View saved configuration file (NVRAM) Router#show startup-config
View IOS version, size of IOS, and free space in FLASH Router#show flash
View CPU utilization Router#show processes cpu
View info about programs in RAM Router#show processes
Display interfaces on router and their status Router#show interface
Display the ip interfaces on router and their status Router#show ip interface
Display which protocols are configured on the router Router#show protocol
Display ip protocol info Router#show ip protocol
Cisco Discovery Protocol
View info of neighboring Cisco devices (routers, switches,etc) Router#show cdp neighbors [ show cdp neighbor detail]
View interface info, default encap, cdp update and holdtime freq Router#show cdp interface
View a neighbors details Router#show cdp entry RouterB
View cdp update and holdtime frequency Router#show cdp
Change update frequency Router#cdp timer 90 [60 sec is default]
Change how long to hold a CDP entry of a neighbor for Router#cdp holdtime 240
Turn off CDP on an interface Router(config-if)#no cdp enable
CDP is enabled globally [CDP is enabled by default] Router(config)# cdp run
David J. Zanich Router Commands Rev 2 Page 1 of 5

2. Managing Configuration Files
Run the initial configuration dialog Router#setup
Reboot the router and reload the startup config from NVRAM Router#reload
Enter global configuration mode Router#config terminal
Copy configuration file in RAM to NVRAM Router#copy running-config startup-config
Copy configuration file in NVRAM to RAM Router#copy startup-config running-config
Erase the configuration file in NVRAM [run initial config dialog] Router#erase startup-config
Copy startup config file from TFTP to NVRAM Router#copy tftp startup-config
Copy startup config file from NVRAM to TFTP Router#copy startup-config tftp
Copy startup config file from TFTP to RAM Router#copy tftp running-config
Copy running config file from RAM to TFTP Router#copy running-config tftp
Backup IOS to file server Router#copy flash tftp
Upgrade the IOS from the file server Router#copy tftp flash
Tell router which IOS file in Flash to boot from Router(config)# boot system flash (ios_filename)
Tell router which IOS to request from the TFTP server (fallback) Router(config)# boot system tftp (ios_filename) tftp_ip_address
Tell router to boot from IOS in ROM Router(config)# boot rom
Password
Set the enable secret password [to enter privileged mode] Router(config)#enable secret Rimmer
Set the enable password Router(config)#enable Rimmer
Set the password for Telnet Router(config)#line vty 0 4 ;0 4 specifies num of telnet sessions
Router(config-line)#login
Router(config-line)# password Holly
Set the console port password Router(config)#line con 0
Router(config-line)#login
Router(config-line)# password Holly
Set the auxiliary password Router(config)#line aux 0
Router(config-line)#login
Router(config-line)# password Holly
Passwords can be encrypted Routerconfig)#service password-encryption
To de-encrypt the passwords Routerconfig)# no service password-encryption
Router Identification
Message of the day Router(config)# banner motd # You are in… #
Give the router a hostname Router(config)#hostname RouterC
Auto-Install
Router broadcasts to get its own TCP/IP address using BOOTP
Router broadcasts again to locate the file server IP addr using TFTP
Router attempts TFTP to get the IP-to-Hostname mapping file Network-confg
If above fails, fallback to 8.3 DOS compatible filename conven Cisconet.cfg
Router attempts TFTP to get its specific Hostname running config {Hostname}-confg
If above fails, fallback to 8.3 DOS compatibile filename conven {Hostname}.cfg
Note: {Hostname}is determined by parsing network-confg file and checking all Hostnames listed against own IP address
Configuring a Serial Interface
Is it DCE or DTE? Router#show controller serial 1
Enter sub interface mode Router(config)#interface serial 1
Set clock rate on DCE Router(config-if)#clock rate 64000 [or clockrate 64000]
Set the bandwidth Router(config-if)# bandwidth 64
Enable the interface Router(config-if)#no shutdown
Check interface status Router#show interface serial 1
Router#show ip interface brief
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3. TCP/IP
Disable IP routing on a router (enabled by default) Router(config)#no ip routing
Put an IP address on an interface Router(config)#interface serial 0
Router(config-if)#ip address 172.16.1.3 255.255.0.0
Router(config-if)#exit
Router(config)#interface ethernet 0
Router(config-if)#ip address 208.10.10.3 255.255.255.0
Configure RIP Router(config)# router rip
Router(config-router)#network 157.2.0.0
Router(config-router)#network 177.2.0.0
Disable RIP routing Router(config)# no router rip
Configure IGRP Router(config)# router igrp 300
Router(config-router)#network 157.2.0.0
Router(config-router)#network 177.2.0.0
Disable IGRP routing Router(config)#no router igrp 300
View the IP routing table Router#show ip route
View RIP Debug Router#debug ip rip
View IGRP Debug Router#debug ip igrp events
Router#debug ip igrp transactions
IPX/SPX
Enable IPX on the router (disabled by default) Router(config)#ipx routing
Enable load balancing Router(config)#ipx maximum-paths 4
Enable IPX on an interface Router(config)#interface serial 0
Set the IPX network number to 2000 use default encapsulation Router(config-if)#ipx network 2000
Ethernet = novell-ether Serial = HDLC
Note: IPX routing is automatically enabled as soon as an IPX address is on an interface.
To force and encapsulation type:
Ethernet_802.3 => novell-ether Router(config-if)#ipx network 2000 encap novell-ether
Ethernet_802.2 => sap Router(config-if)#ipx network 2000 encap sap
Ethernet_II => arpa Router(config-if)#ipx network 2000 encap arpa
Ethernet_SNAP => snap Router(config-if)#ipx network 2000 encap snap
View the SAP tables [list the servers discovered by SAP’s] Router#show ipx servers
View the IPX routing table Router#show ipx route
View traffic statistics [displays RIP and SAP information] Router#show ipx traffic
View the IPX address and encapsulation on an interface Router#show ipx interface
View the routed protocols on the router Router#show protocol
Test host to host connectivity Router#ping ipx <host_address>
Debug Commands
Debug IPX RIP packets Router#debug ipx routing activity
Debug SAP packets Router#debug ipx sap
Turn off the debug command Router#undebug ipx routing activity
Config-Reg
ROM Monitor Mode [prompt will be either: > or rommon>] Router(config)# Config-reg 0x0000
Boot from ROM and enter RXBOOT mode Router(config)# Config-reg 0x0001
[prompt will be: Router_Name(boot)> ]
Boot from ROM & check NVRAM for startup [boot] commands Router(config)# Config-reg 0x0002 [through to 0x000F]
RXBOOT (diagnostics mode, use ‘b’ to continue boot) Router(config)# Config-reg 0x2000
Boot from ROM, use NVRAM (upgrade flash in run-from-flash ) Router(config)# Config-reg 0x2101
Boot from ROM, skip NVRAM (disaster recovery) Router(config)# Config-reg 0x2141
Boot from FLASH, use NVRAM (normal operation) Router(config)# Config-reg 0x2102
Boot from FLASH, skip NVRAM (password recovery) Router(config)# Config-reg 0x2142
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4. Access-Lists
<1-99> IP standard access list
<100-199> IP extended access-list
<200-299> Protocol type-code access list
<300-399> DECnet access list
<400-499> XNS standard access list
<500-599> XNS extended access list
<600-699> Appletalk access list
<700-799> 48 bit MAC address access list
<800-899> IPX standard access list
<900-999> IPX extended access list
<1000-1099> IPX SAP access list
<1100-1199> Extended 48 bit MAC address access list
<1200-1299> IPX summary address access list
View which access lists are applied to an interface Router#show ip interface serial 0
Router#show ipx interface serial 0
Router#show appletalk interface serial 0
View all access lists on the router and list each line of the list Router#show access-lists
View i p access lists only Router#show ip access-lists
View ipx access lists only Router#show ipx access-lists
View appletalk access lists only Router#show appletalk access-lists
IP Standard Access-Lists [1-99] filter on Source Address Template
Deny the subnet 200.10.10.0/24 from entering port E0 Router(config)# access-list 1 deny 200.10.10.0 0.0.0.255
Permit all others [any =0.0.0.0 255.255.255.255] Router(config)# access-list 1 permit any
Implicit deny all at the end of the access list è Router(config)#access-list 1 deny any any
The access list is not operational until bound to an interface Router(config)#interface e0
Router(config-if)#ip access-group 1 in
Deny the host 200.10.10.2/24 from entering port E0 Router(config)# access-list 88 deny host 200.10.10.2
Permit all others [host =200.10.10.2 0.0.0.0] Router(config)# access-list 88 permit any
è
An implicit deny all other traffic is the default line of an access listè Router(config)#access-list 88 deny any any
The access list is not operational until bound to an interface Router(config)#interface e0
Router(config-if)#ip access-group 88 in
IP Extended Access-Lists [100-199] filter on Srce+Dest Address Template, Port, Protocol
Stop all hosts on network 4.4.4.0 from accessing the web (www) Router(config)# access-list 101 deny tcp 4.4.4.0 0.0.0.255 any eq 80
Stop host 2.2.2.2 from telneting to host 3.3.3.3 out E0 Router(config)# access-list 101 deny tcp host 2.2.2.2 host 3.3.3.3 eq 23
Permit all others to have access Router(config)# access-list 101 permit any any
è
An implicit deny all other traffic is the default line of an access listè Router(config)#access-list 101 deny any any
The access list is not operational until bound to an interface Router(config)#interface e0
Router(config-if)#ip access-group 101 out
IPX Standard Access-Lists [800-899] filter on Srce+Dest Address Template
Stop network 7B from getting to network 8000 Router(config)# access-list 801 deny 7B 8000
Allow all other networks [-1 è any network] Router(config)# access-list 801 permit –1 -1
è
An implicit deny all other traffic is the default line of an access listè
The access list is not operational until bound to an interface Router(config)#interface e0
Router(config-if)#ipx access-group 801 out
IPX Extended Access-Lists [900-999] filter on Srce+Dest Address Template, Socket, Protocol
Deny all traffic from network 50 going to network 10 [0=all skts] Router(config)# access-list 901 deny –1 50 0 10 0
Permit all other traffic to all other networks
è
An implicit deny all other traffic is the default line of an access listè Router(config)# access-list 901 permit -1 –1 0 -1 0
The access list is not operational until bound to an interface Router(config)#interface e0
Router(config-if)#ipx access-group 901 out
IPX SAP Access-Lists [1000-1999] filter on Source, Port , Service Name
Allow all packets from network to enter E0 and be included in Router(config)# access-list 1001 permit 11.0000.0000.0001 0
SAP updates across the network. [0 = all service types]
The access list is not operational until bound to an interface Router(config)#interface e0
Stop it coming in Router(config-if)#ipx input-sap-filter 1001
Or stop it going out Router(config-if)#ipx output-sap-filter 1001
David J. Zanich Router Commands Rev 2 Page 4 of 5

5. Frame-Relay
Global Commands
Create a subinterface, or ref a previously created subinterface RouterA(config)#interface serial0.2 <point-to-point|multipoint>
Interface Commands
Enable Frame-Relay on an interface and specify encap type RouterA(config)#int s0
RouterA(config-if)#encapsulation frame-relay <Cisco|IETF>
Note: Cisco is the default encapsulation .
Define a DLCI used for a VC to another DTE RouterA(config-if)#frame-relay interface-dlci 16
Specify type of LMI msgs to the switch (11.2+ autosense) RouterA(config-if)#frame-relay lmi-type <ansi|q933a|cisco>
Statically define a mapping between an IP addr and a DLCI RouterA(config-if)#frame-relay map ip 5.5.5.5 100 broadcast
RouterA(config-if)#frame-relay map ipx 1.0200.bbbb.dddd 502
broadcast
Adjust the keepalive period: how often LMI status msg sent. RouterA(config-if)#frame-relay keepalive 20
Adjust the bandwidth:metric with some routing protocols RouterA(config-if)#frame-relay bandwidth 64000
Show Commands
View LMI information RouterA#show interface serial 0
View PVC traffic statistics:show PVC’s and DLCI’s:sho run RouterA#show frame-relay pvc
View Route Maps (static or dynamic) RouterA#show frame-relay map
View LMI information RouterA#show frame-relay lmi
View frame relay ip statistics RouterA#show frame-relay i p
PPP
Global Commands
Create a username and password for logging in RouterA(config)#username OtherRouter password Lister
Enable PPP on the interface RouterA(config)#int s0
RouterA(config-if)#encapsulation ppp
Interface Commands
Enable authentication (chap or pap) RouterA(config-if)#ppp authentication chap
Specify chap hostname(default to routuer name) RouterA(config-if)#ppp chap hostname MyRouter
Specify chap password (default to enable password) RouterA(config-if)#ppp chap password Rimmer
Specify pap username RouterA(config-if)#ppp pap sent-username Holly
Show Commands
View encapsulation, open LCP’s and more RouterA(config)#show interface serial 0
Debug Commands
View the authentication process RouterA(config)#debug ppp authentication
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